Bwindi Forest National Park Uganda

Western lowland gorilla (Gorilla gorilla gorilla)

Western lowland gorilla (Gorilla gorilla gorilla)

The Western lowland gorillas are among the four (4) subspecies of gorillas together with the mountain gorillas, the Cross River gorillas and the eastern lowland gorillas. It is estimated that close to 600 of this type of gorillas live in captivity like zoos while more than 100,000 gorillas are believed to stay out in the wild n their natural habitat.

Physical Description

This subspecies however is the smallest of them all with an adult Western lowland gorilla weighing about 440 pounds. When standing on two feet they can reach a height ranging between 4.5 to 5.5 feet. Their bodies have black brown far that is shorter compared to other subspecies, they have a more pronounced ridge on their brow as well as longer arms. The infant western lowland gorillas have a characteristic patch of white fur running along their back, while the fully matured Gorillas obtain a shade of silver on their hair.

Diet of Western Lowland Gorillas

These Western lowland gorillas mainly survive on a vegetarian diet that mainly includes roots, shoots, tree barks, pulps and wild berries. On average a fully grown Western lowland gorilla in a single day can eat as much as 18 kg of food. Unlike other primates this subspecies does not have to move long distances to search for food as most of the vegetation they feed on grows rapidly; only covering a distance of about 4 kilometers each day as they look for food. they spend majority of their day feeding and take just a single break during the midday hours during which the young ones play with each other while the adults enjoy a nap.

Among the western lowland gorillas living in captivity a number of unique feeding behaviors have been observed and scientists are still failing to explain them. These include: coprophagy (the habit of eating feces), urine drinking as well as re-ingestion and regurgitation (a habit that involves animals regurgitating some of their food and then eating it again).

Their Habitat / Where to Find Them

The Western lowland gorilla is the most widely prevalent among the gorilla subspecies and these mainly live in the tropical forests of Western Africa and central Africa and can leave up to 40 years within their wild natural habitat. This is the only subspecies of Gorillas that can live in captivity so you will be able to encounter a couple of them in some of the zoos across the globe and there they can live up to 60 years. Within their natural habitat these Gorillas have been recorded to live in Cameroon, Equatorial Guinea, Central African Republic, Gabon, the Democratic republic of Congo, Angola, the republic of Congo and Gabon. They mainly live in the dense parts of forests where availability of the vegetation they eat is good

Behavior of the western lowland gorillas

  1. Family organization

Similar to other gorilla subspecies the Western lowland gorillas live together in communities referred to as troops and these can comprise as many as thirty (30) individuals that is led by a single dominant adult male who is referred to as the silverback (due to the silver ‘like’ hair that covers part of their back). Each troop is comprised of different members among which are the dominant male adult, young males, females as well as their off springs.

  1. Tree climbing

These gorillas despite the fact that they can climb trees choose to spend most of their time on the ground.

  1. Nature of Movement

They mainly move on all four limbs (2 legs and 2 hands) despite the fact that they can stand upright and they do so by shoving themselves forward with the help of the soles of their feet and knuckles.

  1. Leadership

It’s the duty of the troop leader to organize the different activities among which is when to eat, deciding on what is the home range for the troop as well as where to nest for the night.

  1. Protection

The troop leader is mainly concerned with the protection of his entire troop and although these Gorillas have close bonds amongst the troop members, they are from time to time attacked by outsiders especially other males. in case this happens, the dominant troop leader will exhibit his  strength and might by standing upright on his two legs, making aggressive sounds as he charges, throwing about things that are around him and pounding his chest as he powerfully hoots, roars and makes barking sounds.

  1. Serenity

The Western lowland gorillas are generally considered to be very peaceful and will only become aggressive if their peace is disturbed.  In fact on several occasions has it been observed that different troops mix really well with each other without any aggression – simply to feed within their natural habitat. Uniquely this trait of withstanding other troops has only been observed among the Western lowland gorilla subspecies. Members of the troop hardly get into conflicts or even hold grudges for a long duration – a thing that is common among chimpanzees. However the silverback intervenes in any rising conflict that may come up especially between the females

  1. Mating

Within the Western lowland gorillas the mating process is initiated by the females while ovulating. It is the responsibility of the dominant male to cater to all sexual requirements of the female in his troop while they are ovulating.

  1. Reproductive maturity

The females reach reproductive maturity at approximately eight (8) years old and at the time they normally leave their birth- troop and join another or simply hook up with a lone silverback. They do so to avoid conflict other mature females within the troop which may come up as a result of competing for attention and favor before the silverback. The gestation period of the western lowland gorilla is nine (9) months after which she will give birth. Although they never reach menopause (according to Sylvia Atsalis a primatologist based at Brookfield Zoo – Chicago) they may give birth to 4 to 6 off springs in the lifetime at intervals of four (4) years.

On the other hand the young males on maturity also tend to leave their birth- troop to avoid being looked at by the existing dominant silverback as a threat. On leaving the troop the young male will join a group of other lone males or simply stay by itself until a female chooses him to begin another family.

  1. Communication

the western lowland gorillas are considered to be quiet most of the time however, they have a complex range of vocalization that includes more than twenty (20) various hoots, screams and barks each having a distinct meaning. According to those that have been observed while in captivity they have displayed great intelligence and easily learned the basic sign language used by man.

Top 5 Threats to the Survival of Western Lowland Gorillas

The International Union for Conservation of Nature (IUCN) classified the Western lowland gorillas as critically endangered despite the fact that this is the most widespread gorilla subspecies as it faces very many threats as highlighted below.

  1. Deforestation

This activity has not only destroyed the natural habitat of the gorilla but also made it easier for poachers who hunt the Western lowland gorilla for bush-meat. More than 75% of these gorillas are living in areas that are unprotected a thing that puts them in great danger of poachers.

  1. Disease

Various diseases have greatly affected the overall population the western lowland gorillas among which are human diseases such as the basic flu to which the gorilla has no immunity against. In addition Ebola is another killer disease which primate experts believe that back in the early 2000’s led to the death of nearly 10% of their total population. As an example between 2002 and 2004 an Ebola outbreaks that happened in the republic of Congo killed nearly 30% of the total population of Western lowland gorillas living in that area and the disease spread wildly between them as a wildfire since within this subspecies different troops can interact easily with each other.

  1. Human Encroachment on Their Habitat

Humans have been a very big threat to the existence of the western lowland gorilla as they have continuously encroached on their natural habitat inform of clearing land for human settlement, farming as well as grazing. This has further pushed these Gorillas deeper into the forest giving them a smaller area to occupy.

  1. Climatic Change

The global change in climate has not only affected mankind but also affected the Gorillas as the warm temperatures consequently dry out the vegetation on which these Forest Giants depend for food and more so make the dry forest even more vulnerable to fires.

  1. Poor Management and Corruption

we shouldn’t forget that majority of the countries on the African continent where these gorillas live have suffered from civil unrest and because of poor management of the forest reserves as well as corruption within the government authorities that would manage these Forests, poaching has continued to take place as well as humans taking over the would be gazetted forest reserves that would serve as habitant to this subspecies. The failing policies that are in place within such countries have greatly lead do a decline in the population of western lowland gorillas. in contrary to countries like Uganda and Rwanda where the mountain gorilla subspecies is found which have very stringent policies regarding Forest management have seen an increase in the population of the mountain gorilla subspecies.

Conservation of the western lowland gorilla

This subspecies over the years has been safeguarded by both international and national laws however these have not been strongly enforced in the past. Today a number of international conservation groups have come out to work with both the local community as well as the national authorities within the respective countries where these gorillas are found to reinforce the penalties directed towards poaching as well as enhance proper planning for the use of land with an aim of protecting the natural habitat of these gorillas. Currently various international wildlife organizations such as the World Wild Fund for nature (WWF), Zoos worldwide together with Wildlife Conservation Society (WCS) have positively responded to see that they conserve the survival of the western lowland gorilla subspecies. The World Wide Fund for Nature began a Great Apes Program on the African continent to assist in the conservation of the different gorilla subspecies by supporting gorilla tracking programs, strengthening the gazette areas as well as enhancing sustainable development through availing an Ebola vaccine. The vaccine program is currently active in various western lowland gorilla sanctuaries such as the Lobeke National Park found in Cameroon, Nouabale-Ndoki in the Congo and Dzanga Sangha protected area found in Central African Republic.

Trekking Western Lowland Gorilla

Similar to their counterparts the mountain gorillas the Western lowland gorillas can also be trekked as one of the tourist activities on a Safari in Africa. The activity includes walking for several hours within the thick forested areas in remote Africa as you search for them in their natural habitat since they live deeper within the verdant forests. Majority of them have not been habituated and it’s for that reason the tourists who headed out to see them normally have to hide in various enclosures and patiently wait for the Gorillas to come out in the open. Nonetheless below are the various destinations where Western lowland Gorilla trekking can be done.

Cabinda enclave found in Angola

Odzala National Park found in Congo Brazzaville

Monte alen National Park found in Guinea

Moukalaba-Doudou National Park found in Gabon

Dzanga-Ndoki National Park found in Central African Republic

Lefini Reserve found in Congo brazzaville